The invention relates to a magnetic head having a head face and a thin-film structure, with a magnetoresistive element and a flux-guiding element of a magnetically permeable material having a relatively high relative magnetic permeability, a peripheral area of the magnetoresistive element extending opposite the flux-guiding element and an electrically insulating intermediate layer being present at least between the peripheral area and the flux-guiding element.
A magnetic head of this type is known from U.S. Pat. No. 4,425,593 (PHN 9357, herewith incorporated by reference). The known magnetic head is a read head which is used for detecting information-representing magnetic fields on a magnetic recording medium moving with respect to the magnetic head, particularly a magnetic tape. The magnetic head has a head face and comprises a substrate of a ferrite which constitutes a magnetic yoke, together with two aligned layer-shaped flux guides of a material having a relatively high relative magnetic permeability, for example, a nickel-iron alloy whose relative magnetic permeability is typically 1000. The magnetic head also comprises an elongate layer-shaped magnetoresistive element (MR element) provided with equipotential strips which has contact faces at two opposite ends and has such a magnetic anisotropy that the easy axis of magnetization at least substantially coincides with its longitudinal axis. The MR element is arranged within the magnetic yoke in such a way that a gap, which is present between the flux guides, is bridged by the MR element. The flux guides have facing end portions which are present opposite peripheral areas of the MR element extending parallel to the head face. An insulation layer of quartz extends both between the ferrite substrate and the electrically conducting MR element and between the MR element and the electrically conducting flux guides. Consequently, the known magnetic head incorporates a non-magnetic, electrically insulating material in the overlap areas constituted by the peripheral areas of the MR element and the facing end portions of the flux guides.
A drawback of the known magnetic head is that, due to the distance caused by the non-magnetic material between the peripheral areas of the MR element and the facing end portions of the flux guides, only a small portion of the magnetic flux originating from the magnetic recording medium is actually passed through the MR element during operation. In other words, the known magnetic head has a low efficiency.